Related Experiment Video
Updated: Apr 6, 2026
09:00
Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
10.6K
Electrically Tunable Magnetism in Magnetic Topological Insulators
Jing Wang1, Biao Lian1, Shou-Cheng Zhang1
1Department of Physics, McCullough Building, Stanford University, Stanford, California 94305-4045, USA.
Physical Review Letters
|August 1, 2015
Summary
We predict electric-field control of magnetism in topological insulators. This could enable voltage-controlled magnetic random-access memory and novel spintronic devices.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Phenomena
Background:
- Controlling magnetic properties of topological insulators is crucial for fundamental science and applications.
- Insulating magnetic topological insulators offer unique platforms for exploring exotic electronic and magnetic phenomena.
Purpose of the Study:
- To predict the electric-field control of ferromagnetism in thin films of insulating magnetic topological insulators.
- To explore the potential for electric-field-induced magnetic quantum phase transitions.
- To propose device applications leveraging these phenomena.
Main Methods:
- Theoretical prediction of electric-field effects on band inversion and magnetic susceptibility.
- Modeling of magnetic quantum phase transitions.
- Device design incorporating chiral edge states and ferromagnetism.
Main Results:
- Electric fields can decrease band inversion, reducing magnetic susceptibility and modifying magnetism.
- Electric fields can induce a quantum phase transition from ferromagnetism to paramagnetism.
- A transistor device demonstrates electric-field control of dissipationless chiral edge transport.
Conclusions:
- Electric-field control of magnetism in topological insulators is feasible.
- These findings pave the way for voltage-based writing in magnetic random-access memories.
- Simultaneous electrical control of magnetic order and edge transport opens avenues for advanced electronic and spintronic applications.
More Related Videos
Related Concept Videos
01:28Types Of Superconductors
1.8K
A superconductor is a substance that offers zero resistance to the electric current when it drops below a critical temperature. Zero resistance is not the only interesting phenomenon as materials reach their transition temperatures. A second effect is the exclusion of magnetic fields. This is known as the Meissner effect. A light, permanent magnet placed over a superconducting sample will levitate in a stable position above the superconductor. High-speed trains that levitate on strong...
1.8K
01:31Ferromagnetism
3.5K
Materials like iron, nickel, and cobalt consist of magnetic domains, within which the magnetic dipoles are arranged parallel to each other. The magnetic dipoles are rigidly aligned in the same direction within a domain by quantum mechanical coupling among the atoms. This coupling is so strong that even thermal agitation at room temperature cannot break it. The result is that each domain has a net dipole moment. However, some materials have weaker coupling, and are ferromagnetic at lower...
3.5K
01:27Magnetic Fields
7.9K
A moving charge or a current creates a magnetic field in the surrounding space, in addition to its electric field. The magnetic field exerts a force on any other moving charge or current that is present in the field. Like an electric field, the magnetic field is also a vector field. At any position, the direction of the magnetic field is defined as the direction in which the north pole of a compass needle points.
A magnetic field is defined by the force that a charged particle experiences...
A magnetic field is defined by the force that a charged particle experiences...
7.9K
01:30Paramagnetism
3.2K
Paramagnets are materials with unpaired electrons that possess a finite magnetic moment. In the absence of a magnetic field, these moments are randomly oriented, and thus the net moment is zero. Under an external field, a torque acting on the moments tends to align them along the field's direction. However, the random thermal motion of electrons produces a torque opposite to the external field and tries to disorient the moments. These two competing effects align only a few moments along the...
3.2K
01:26Diamagnetism
3.4K
Materials consisting of paired electrons have zero net magnetic moments. However, when these materials are placed under an external magnetic field, the moments opposite to the field are induced. Such materials are called diamagnets. Diamagnetism is the response of the diamagnets when placed in an external magnetic field.
Diamagnetism was discovered by Anton Brugmans in 1778 when he observed that bismuth gets repelled by magnetic fields, thus theorizing that diamagnets get repelled by magnets....
Diamagnetism was discovered by Anton Brugmans in 1778 when he observed that bismuth gets repelled by magnetic fields, thus theorizing that diamagnets get repelled by magnets....
3.4K
01:24Potential Due to a Magnetized Object
885
Magnetic dipoles in magnetic materials are aligned when placed under an external magnetic field. For paramagnets and ferromagnets, dipole alignment occurs in the direction of the magnetic field. However, the dipoles align opposite to the field in the case of diamagnets. This state of magnetic polarization due to the external field is called magnetization. Magnetization is defined as the dipole moment per unit volume. It plays a similar role to polarization in electrostatics.
The vector...
The vector...
885